In performing an electrical property test on a plurality of devices formed on a semiconductor wafer by a testing apparatus, a plurality of electrode pads formed on the respective devices of the semiconductor wafer are electrically contacted with a plurality of probes. Herein, the alignment of the plurality of electrode pads of the respective devices with the plurality of probes is carried out by moving the semiconductor wafer in a horizontal direction with respect to the plurality of probes, and then the semiconductor wafer is moved up toward the plurality of probes, thereby electrically contacting the plurality of electrode pads of the respective devices with the plurality of probes.
Hereinafter, one example of a conventional contact method for electrically contacting a plurality of electrode pads with a plurality of probes will be described with reference to FIGS. 7A and 7B. FIG. 7A shows a semiconductor wafer 1 with one electrode pad 2 formed thereon and one probe 3 which are zoomed in. In order to electrically contact electrode pad 2 with probe 3, a plurality of contact parameters have to be set. The contact parameters include, as shown in FIG. 7A, a height [a contact height (h)] of an electrode pad of a semiconductor wafer when electrode pad 2 is contacted with probe 3, an extent of electrode pad 2 coming into probe 3 after the contact [an overdrive (o)], and an extent of electrode pad 2 being taken away from probe 3 during the movement toward the next device [a downward amount]. Also, a speed of a semiconductor wafer and a position (c) where the speed is changed (a point where the speed is changed from a solid line arrow to a dashed line arrow), which are required to securely stick probe 3 into electrode pad 2, are necessary as contact parameters. Also, in some cases, the number of times electrode pad 2 contacts with probe 3 may be required as a contact parameter. All of these contact parameters are set by inputting their respective values through a screen of a display device attached to a testing apparatus. The contact operation of a semiconductor wafer is set by contact parameters, and thereby the test on a device is carried out without damage to electrode pad 2 and probe 3. The technologies on contact parameters are disclosed in the patent publications mentioned below.
Japanese Laid-Open Patent Publication HEI No. 11-145221 discloses a method for electrically securely contacting an electrode pad with a probe, in which the electrode pad is electrically contacted with the probe by being moved up to a first overdrive state, the electrode pad is slightly moved down, and then the electrode pad is moved up to a second overdrive state. In this case, the extent of the first and second overdrive or the electrode pad's downward movement is set as a contact parameter.
Also, Japanese Laid-Open Patent Publication No. 2007-095753 discloses that, in order to prevent an electrode pad from being damaged by a probe, the electrode pad is contacted with the probe with an upward movement speed which is significantly slowed down just prior to the contact of the electrode pad with the probe, and then the electrode pad is separated from the probe and the electrode pad is contacted with the probe again with an upward movement speed which is equal to or slightly higher than the upward movement speed prior to the contact. In this case, a plurality of upward movement speeds are set as contact parameters.
Also, Japanese Laid-Open Patent Publication No. 2007-523350 discloses that, in order to prevent an electrode pad from being damaged by a probe, the probe is disposed adjacently to the electrode pad, and the probe and the electrode pad electrically contact with each other by being moved in a horizontal direction with respect to each other. In this case, the distances where a semiconductor wafer and the probe are moved with respect to each other or the distances where a semiconductor wafer and the probe are moved in a horizontal direction until a leading end of the probe is disposed slightly below the upper surface of the electrode pad, are set as contact parameters.
However, in the conventional method for setting contact parameters, as shown in FIGS. 7A and 7B, although all of the contact parameters are set by using a screen of a display device attached to a testing apparatus, there is a limitation in the amount of information which can be displayed on the screen of the display device of the testing apparatus. Thus, all of the contact parameters cannot be set through one screen, and thereby there is no choice but to divide the contact parameters into a several groups and to set them by changing the display screen several times, as shown in FIG. 7B. In this case, since the display screen is changed into small screens to set the contact parameters, it is difficult to check the relationship between contact parameters set on the respective screens and the checking requires a long time. Moreover, it is difficult to understand the entire contact process of a semiconductor wafer with a probe. Also, the three patent publications mentioned above do not disclose a method for setting contact parameters.